I dont even know if this is the right term "safe-volume"....but I have just changed to KDE and before I used MATE. In MATE when I plugged in my earphones.....the system immediately set the volume to, more or less, 60%. Which was great to protect my ears from loud noise if I previously had the volume set to 100%.
Is there a way to set this in KDE?
UPDATE. I have found a solution. veromix widget in KDE can be set for headphones.